This invention relates to a tracking apparatus and a tracking method, and more particularly to a tracking apparatus and a tracking method suitable for use, for example, with a supervisory camera, a television conference system, a video camera which automatically tracks an imaging object or a like apparatus.
A video camera system has already been proposed wherein a pan driving mechanism and a tilt driving mechanism are used to automatically track an imaging object as an object of tracking so that the imaging object may be displayed, for example, at a central location of a display screen.
In a video camera of the type described above, for example, a reference measurement frame is provided at a central location of a display screen (image photographed or imaged by a video camera), and imaging is performed so that the imaging object as an object of tracking may be included in the reference measurement frame and the thus imaged image is stored into a memory, that is, an imaging object to be automatically tracked is set. Thereafter, from an image imaged by the video camera, the stored imaging object is detected, and when the imaging object is detected successfully, panning and tilting are performed so that the imaging object may be displayed at a central location of the display screen.
Further, when the imaging object is detected successfully, a region of the image outputted from the video camera which is occupied by the imaging object is displayed, for example, in a white saturated form so that the position of the imaging object may be recognized by a user.
On the other hand, if the imaging object is not detected successfully, that is, when the imaging object is missed, the image outputted from the video camera is displayed as it is.
A video camera system which performs such automatic tracking can be applied, for example, to a supervisory camera, a television conference system of the automatic speaker tracking type which automatically tracks any speaker and like systems, and is further used as effective means which allows an unmanned security system or allows hand-free photographing.
By the way, in a related art video camera, when a user intends to set an imaging object to be tracked, the user must manually operate the video camera so as to effect panning and/or tilting so that the image object may be included in a reference measurement frame.
In particular, although the user need not manually operate the video camera after the imaging object is set, in order to set the imaging object, the user must manually operate the video camera, which is cumbersome.
Further, with a related art video camera, if it becomes impossible to detect an imaging object any more during automatic tracking, then an image outputted from the video camera is not partially saturated with white but is displayed as it is as described above, and in this instance, it is difficult for the user to recognize that the imaging object is not detected.